This disclosure relates generally to online systems, and in particular to presentation of advertisements to users of an online system.
An online system allows its users to connect to and communicate with other online system users. Users may create profiles on an online system that are tied to their identities and include information about the users, such as interests and demographic information. The users may be individuals or entities such as corporations or charities. Because of the increasing popularity of online systems and the increasing amount of user-specific information maintained by online systems, such as social networking systems, an online system provides an ideal forum for advertisers to increase awareness about products or services by presenting advertisements to online system users.
Presenting advertisements to users of an online system allows an advertiser to gain public attention for products or services and to persuade online system users to take an action regarding the advertiser's products, services, opinions, or causes. Many online systems generate revenue by displaying advertisements to their users. Frequently, online systems charge advertisers for each presentation of an advertisement to an online system user (e.g., each “impression” of the advertisement) or interaction with an advertisement by an online system user.
Metrics describing the effectiveness of advertisements presented to online system users allow advertisers to present advertisements more likely to be interacted with by online system users. For example, metrics measuring the effectiveness of an advertiser's advertisements in driving user visitation to physical sites, such as retail stores, allow advertisers to better leverage advertisements presented by online systems. Conventionally, advertisers poll potential customers to determine whether they have been exposed to particular advertisements or whether exposure to particular advertisements caused them to visit certain physical locations associated with the advertisements to obtain metrics describing advertisement effectiveness.
However, polling potential customers often results in unreliable information because potential customers often have limited recall regarding how they became aware of an advertiser's products or how they were enticed to visit a physical location. Additionally, polling potential customers is intrusive to the potential customers, which decreases the likelihood of potential customers responding to polling. The limited reliability of information received by polling as well as the low response of potential customers to polling limits the accuracy of conventionally generated advertising metrics.